Straightening machine



y 1, 1960 J. H. ROHLFS 2,938,563

STRAIGHTENING MACHINE Filed June 17, 1959 5 Sheets-Sheet 1 INVEN TOR. JOHN H. ROHLFS BY 9Q %M ATTORNEYS J. H. ROHLFS 2,938,563

STRAIGHTENING MACHINE 5 Sheets-Sheet 2 May 31, 1960 Filed June 17, 1959 JOHN H. ROHLFS ATTORNEYS May 31, 1960 J. H. ROHLFS 2,938,563

STRAIGHTENING MACHINE I Filed June 17, 1959 5 Sheets-Sheet 3 IN V EN TOR. JOHN H. ROHL F5 ATTORNEYS V May 31, 1960 J. H. ROHLFS 2,938,563

STRAIGHTENING MACHINE Filed June 17, 1959 5 Sheets-Sheet 4 647 6 2q 17 5 145 l2q 34:1 652 6 4:: 724: 7

Fla. 8 Z

IN V EN TOR. JOHN H. ROHLFS BY M ATTORNEYS M'aLy 31, 1960 J. H. ROHLFS STRAIGHTENING momma 5 Sheets-Sheet 5 Filed June 17, 1959 FIG [0 INVENTOR. JOHN H ROHLFS ATTORNEYS S'IRAIGHTENING MACHINE John 'H. Rohlfs, Torrington, Conn., assignor to Special Machine Company, Winsted, Conn., a partnership Filed June 17, 1959, Ser. No. 820,904

18 Claims. (Cl. 153-32) This invention relates to a machine for straightening elongated workpieces.

It has been a conventional practice in the design of straightening machines to provide for the axial passage of elongated workpieces to be straightened through the machine. Such machines may be suited to the straightening of wire, shafts, various types of tubing, and other workpieces having uniform cross sections throughout their length. These machines, however, are not at all suited to the straightening of workpieces having nonuniform cross section throughout their length. That is, the machines ordinarily incorporate various work holding or engaging means particularly adapted for the axial passage of workpieces of uniform cross section throughout their length. Obviously, workpieces of nonuniform cross section throughout their length cannot be accommodated by these work holding or engaging means.

It is the general object of the present invention to provide a straightening machine which is particularly adapted to accommodate workpieces of nonuniform cross section throughout their length, and which includes means for rotating the workpiece and means for selectively holding the workpiece straight and bending it in order to effect straightening of the same with no substantial endwise movement thereof.

The drawings show two embodiments of the invention and such embodiments will be described, but it will be understood that various changes may be made from the constructions disclosed, and that the drawings and description are not to be construed as defining or limiting the scope of the invention, the claims forming a part of this specification being relied upon for that purpose.

Of the drawings:

Fig. 1 is a plan view of a straightening machine constituting a presently preferred embodiment of the invention, the machine being shown with a workpiece held straight therein.

Fig. 2 is a plan view of the straightening machine of Fig. 1 with the workpiece bent to an undulating shape.

Fig. 3 is a side elevation of the straightening machine.

Fig. 4 is a fragmentary, longitudinal, vertical section taken as indicated by the line 4-4 in Fig. 1.

Fig. 5 is a fragmentary, transverse, vertical section taken as indicated by the line 5-5 in Fig. 1.

Fig. 6 is a schematic illustration of an exemplary electrical control for the straightening machine.

Fig. 7 is a fragmentary plan view of a laterally movable work holder incorporated in a straightening machine constituting another embodiment of the invention.

Fig. 8 is a vertical transverse section taken as indicated by the line 8-8 in Fig. 7.

Fig. 9 is a fragmentary plan view of a laterally fixed work holder utilized with the movable work holder of Fig. 7.

Fig. 10 is an end view partially in section of the work holder of Fig. 9.

Generally speaking, the straightening machine of the present invention comprises at least three work holders nite States Patent 0 which are arranged in a longitudinal series, and which are respectively adapted to engage successive longitudinally spaced portions of a workpiece having a nonuniform cross section throughout its length. The work holders are collectively adapted to effect longitudinal alignment and relative lateral displacement of the said workpiece portions without substantial endwise movement of the workpiece. Also included in the machine is a means for rotating the workpiece while the said portions thereof are engaged by the holders.

In the straightening operation, the workpiece is first held straight by the work holders and is rotated by said last-mentioned means. The portions of the workpiece engaged by the holders are then displaced laterally with the workpiece rotating to bend the same a selected amount. Thereafter, with the workpiece still rotating, its said portions are brought back into longitudinal alignment and the workpiece is held straight. As a result of this operation, the workpiece is caused to assumea permanent straight set with a high degree of accuracy. No substantial endwise movement of the workpiece occurs in the course of the straightening operation.

In Figs. 1, 2 and 3 of the drawings, a nonuniform elongated workpiece W is shown in the straightening machine which constitutes the presently preferred embodiment of the invention. The workpiece W is a hollow tapered steel tube or shaft of the type used in the manufacture of golf clubs and the said straightening machine is particularly adapted to accommodate the same. It is to be understood, however, that other types of nonuniform workpieces may be accommodated in straightening machines embodying the present invention. For example, circular or partially circular elongated workpieces having one or more portions which are of different diameters, but wherein each portion is of uniform diameter, may be straightened in a machine constructed in accordance with the invention. Similarly, elongated workpieces having cross sections which are approximately uniform in size throughout their length but which are nonuniform in shape maybe accommodated in a straightening machine embodying the present invention.

Referring particularly to Figs. 1 and 2, it will be noted that the straightening machine illustrated therein includes a plurality of work holders indicated generally at 10. The said work holders are shown arranged in a longitudinal series on a substantially horizontal flat surface 12 of a machine frame indicated generally at 14. The frame 14, as best illustrated in Fig. 3, comprises upper and lower sections 16 and 18 which may be welded or otherwise rigidly connected. The aforementioned surface 12 is formed on the upper frame section 16 and is exposed upwardly. The lower frame section 18 supports the upper section 16 and is provided with a pair of wheels 20, 20 (one shown) so that the machine may be conveniently moved from one location to another.

In accordance with the invention, the work holders of the straightening machine are adapted to engage successive longitudinally spaced portions of the workpiece and they are also adapted for relative lateral movement so as to effect longitudinal alignment of said portions of the workpiece and relative lateral displacement thereof. In the embodiment of the invention shown in Figs. 1 and 2, there are two separate groups of work holders included in the plurality of holders designated generally by the reference numeral 10 and the work holders of said two groups are arranged alternately in the aforementioned longitudinal series. A first group of work holders comprises eight similar holders, each of which is designated by a reference numeral 22 and a second group comprises seven similar work holders, each designated by a reference numeral 24. The total number of work holders and the number in each group of work holders Patented May 31, 1960 ass-ease isoptional and is, of course, dependentto some extent on the length of the workpiece to be straightened. As previously mentioned, however, there are at least three work holdersarranged: in a'longitudinal series. T

Each of the workiholders 22 of the first group is supported on the aforementioned flat frame surface 12 and issecured thereto so as to be fixed. againstlateral movement and to hold the portionsof the: shaft W'engaged thereby in longitudinak alignment. As'b'est illustrated in Fig. 4, each of the work holders 22 has a base portion 26 which on the frame surface 12 and which. has formed integrally therewith an upwardly extending housing portion 28. The base portion 26 of each of the work holders 22 extends transversely of: the machine from opposite sides of the" housing portion 28 thereof; As best shown" in'Figs. l and 2, two longitudinally extending clamping bars 30, 30 are disposed: respectively on opposite sides of the housing portions 28, 28 and above the extending base portions 26, 26 of the eight work holders 22; 22 arranged in a longitudinal series on the frame surface 12. Two clamping screws 32, 32 associated with each of the work holders 22', 22' extend respectively through two suitable openings in the base portion 26 of the work holder and through suitable openings in the clamping bars 30, 36 to secure saidbars and work holders to the machine frame 14. Asbest shown in Figs. 1, 2 and 5, a longitudinally extending slot 33- is provided in theframe surface 12 at one side of the work holders 22, 22 and the work holders 24, 24'.- Eight backing blocks 35-, 35 entered in the slot 33 respectively engage the base portions 26, 26 of the work holders 22, 24 to further secure the said holders against lateral movement thereof in one direction.

The work holders 24, 24 arranged alternately in longitudinal series with the work holders 22, 22, are shown as being of somewhat similar construction. That is, each of the work holders 24, 24 has a base portion 34 which rests on the frame 12 and which is similar to the base portion 26 of a work holder 22 and each of said holders has an upwardly extending housing portion 36 similar to a housing portion 28. As best illustrated in Figs. 1 and. 2, the base portions 34, 34 of the work holders 24, 24 extend transversely of the machine from opposite sides of the housing portions 36, 36 thereof andare disposed beneath the longitudinally extending clamping bars 30,

30. The said base portions are not, however, clamped between the said bars and the flat frame surface 12 so as to be held in fixed position. Rather, they are free to slide laterally on the frame surface 12 with their said base portions moving beneath and relative to the said bars. Longitudinal movement of the work holders 24, 24 is, however, prevented. As best shown in Fig. 4, the base portions 26, 26 of adjacent work holders 22, 22 abut the base portions 34, 34 and prevent such move ment.

The manner in which the work holders 22, 22 of the first group and the work holders 24, 24 of the second group engage theworkpiece may vary widely within the scope of the invention. In the preferred embodiment of the invention shown, each of the work holders 22, 22 and-each of the Work holders '24, 24 isprovided with a rotatable member 38 which has a longitudinally extending opening 40 therein. The openings 40, 40 in the work holders are adapted to receive and substantially'fi-t successive longitudinally spaced portions of the shaft W. That is, the said openings 40, 40 are of substantially circular cross section and are of progressively smaller diameter when viewed from left to right in Figs. 1 and 2. Thus, the shaft W may be positioned in the work holders 22, 22 and the work holders 24, 24 by entering its smaller end portion in said openings in sequence from the left-hand end of the machine. In Figs. 1, 2 and 3, the shaft Wis shown so entered in the openings 40, 40 of the rotatable members 38, 38 of the work holder's.

Each of the openings 40, 40, as best shown'in Fig. 4,

is preferably of varying diameter throughout its length. More specifically, each of said openings is preferably of a relatively small diameter at a central portion 42 thereof and of a larger diameter at its end portions. As shown, the walls of the openings gradually curve from the central portions 42, 42 thereof to the end portions thereof in a partially circular path. The diameter of each opening 49 at its central portion 42 is determined by the diameter of that portion of the shaft W which is to be received by the opening when the shaft. is entered in. the said openings as described. The radii of curvature of the walls of the openings 40, 40 from. their central portions 42, 42 to their end portions are somewhat critical as will be described further hereinafter.

While the rotatable members 38, 38 may take various forms, they are shown as taking the form of bushings supported for rotation within two ball bearing units 44, 44.- As best shown. in- Fig. 4, each of the rotatableniembers or bushings 38, 38 is provided externally with annular' recesses 46, .46 at opposite ends thereof. The recesses 46,. 46 respectively receive the inner races ofthe ball bearing units 44, 44, the said units being spaced axially within the housing portions 28, 28- of the work holders 2'2, 22 and the housing portions 36, 36 of the work holders 24,. 24. The assembly comprising the ball bearing units 44, 44 and the bushing 38 is held within the said housing portionsof'the work holders 'by suitable snap rings 48, 48.

It will: also be observ'ed in Fig. 4 that. each of the bushings 38, 38 in the work holders 22, 22 has associated therewith a ring gear 52. The gear 52 is disposed between the ball bearing units 44, 44 and surrounds and is secured to the bushing. 38' by means of a suitable key connection. indicated at 54.. The gears 52, 52 and the associated bushings 38, 38 are rotatably driven by a plural'ity' of gears'56, 56'keyed to a longitudinal shaft 58 and respectively spaced therealong soas to engage the *gears'52, 52. The shaft 58 is disposed beneath the portion of the machine frame 14 which forms the fiat surface 12 and the gears 56, v56 extend upwardly through suitable openings 60', 66 in saidframe portion and openings 62, 62 in the base portions 26, 26 of the work holders 22, 22 into engagement with the gears 52, 52.

From the foregoing it will be apparent that the shaft 58 is adapted to rotate the gears 56, 56 and the gears 52, 52 whereby to rotate the bushings 38, 38 in the work holders 22, 22. It will be further apparent that rotation of the shaft W be-thus effectedlfthe' said shaft is urged into' friction tight engagement with the central portions 42, 42 of the .walls of the openings 49, 40 in said bushings when itis entered in the openings 40, 40 of all of the bushing's'38, 38 in they manner described above, all of the bushings as well as the shaft will be rotated when the bushings in the work holders 22, 22 are so driven. While rotation of the shaft or other workpiece is essential',-' it will be; understood that other means for efiecting such rotation may be provided within the scope 'of the invention;

As mentioned previously, the work holders 24, 24 are slidable laterally or transversely on the framesurface 12. As will beexplained more fully hereinafter, the said work holders are moved laterally in'unison and in the same direction so thatportions of the; shaft W in their bushings 38,38 are displacedlaterally with: respect to the portions in the bushings of the work holders 22', 22 to bend the shaft to an undulating shape from end to end. Thus, it will be seen that-the lateral displacement of the shaft portions operated on by the work holders 24,24 is substantially rectilinear andtakes place in the same direction and in a common plane. The invention is, however, not to be construed as so limited. It is contemplated that relative lateral displacementof portions of a. workpiece to be straightened may be effected in various other ways Thedisplacement need not be linear'nor does it have to be in the same direction or in a common plane.

Lateral movement of the work holders 24, 24 in unison and in the same direction may obviously be provided for in various ways. In accordance with the presently preferred practice, power operated cam means associated with the work holders 24, 24 effect lateral sliding movement of the said holders. As best illustrated in Fig. 5, the base portion 34 of each of the work holders 24, 24 is provided with a cam follower which may take the form of a roller 64 rotatable about a vertically extending pin 66. The pin 66 is journaled at opposite ends in suitable lugs 68, 68 formed on the base portion 34. Each of the rollers 64 has associated therewith a cam bar 70. As best shown in Figs. 1 and 2, the cam bars 70, 70 are each connected to and movable longitudinally with an actuating bar 72. The cam bars 70, 70 are spaced longitudinally along the actuating bar 72 so as to engage their corresponding rollers 64, 64 and each of said cam bars presents a flat surface to its roller which is inclined to pro vide for lateral displacement of the roller with longitudinal movement of the actuating bar 72 and the cam bar. More specifically, each cam bar 79 is substantially rectilinear in shape and has a partially circular recess 74 adjacent one end which is adapted to receive a portion of a vertically extending dowel or pivot pin 76. An opposite portion of the dowel or pivot pin 76 is received in a suitable partially circular recess formed in the actuating bar 72. At the opposite end of the cam bar, an adjusting screw 78 extends laterally through a suitable threaded opening therein and engages the actuating bar 72 to hold the said end of the bar in spaced relation with the actuating bar. A binder screw 80 fixedly secures the adjusting screw 78 in the cam bar. Obviously, the adjusting screw 78 may be turned to pivot the cam bar 70 about the dowel or pin 76 whereby to vary the angle of inclination of the surface of said bar which engages the corresponding roller 64. As best shown in Fig. 5, the roller 64 is held in engagement with the said surface of the cam bar by means of a biasing spring 82 which is seated in a suitable opening 84 in the clamping bar 38 on the side of the work holder opposite the said roller. The spring 82 engages the upwardly extending housing portion 36 of the work holder and biases the same toward the cam bar 70 whereby to maintain engagement between the roller 64 and said cam bar.

From the foregoing, it will be apparent that the actuating bar 72 may be moved rightwardly from the position shown in Fig. 1 to the position shown in Fig. 2 to effect lateral movement of the Work holders 24, 24 from a first or normal position as shown in Fig. 1 to a second position as shown in Fig. 2. Thereafter, leftward movement of the said bar may be effected to return the work holders 24, 24 to the position shown in Fig. 1. A longitudinal series of backing rollers 86, 86 is provided to prevent lateral or transverse movement of the actuating bar 72 and a suitable cover plate 83 for said bar and rollers isosecgred to the frame 14 by means of suitable screws In operation of the straightening machine, a shaft W is entered in the openings 40, 40 in the bushings of the work holders 22, 22 and in the openings 46, 49 in the bushings of the work holders 24, 24 with the latter Work holders in their first or normal position as illustrated in Fig. 1. In such position of the holders 24, 24, the openings 40, 40 in their bushings 38, 33 are aligned longitudinally with each other and with the openings 46, 40 in the bushings 38, 38 of the work holders 22, 22. In entering the shaft in the openings 46, 46, it is urged rightwardly with sufficient force to effect friction tight engagement of its periphery with the walls of the openings 40, 40 at their central portions 42, 42. The shaft W is then rotated by turning the rotatable drive shaft 58 whereby to rotate the bushings 38, 38 in the work holders 22, 22 through the gears 56, 56 and the gears 52, 52.

While the shaft W is rotating, the actuating bar 72 is moved rightwardly from the position shown in Fig. l to the position shown in Fig. 2. This results in simultaneous lateral sliding movement of the work holders 24, 24 from their first or normal position to the second position as shown in Fig. 2. In their second position, the work holders 24, 24 effect lateral displacement of the portions of the shaft W within their bushings to bend the shaft to an undulating shape from end to end. As shown in Fig. 2, the lateral displacement of the portions of the shaft within the bushings of the work holders '24, 24 is substantially equal. However, it is to be observed that different lateral displacements of the various portions of the shaft within the bushings 38, 38 of the work holders 24, 24 may be effected. That is, the adjusting screws 78, 78 associated with the cam bars 70, '70 may be utilized to provide for difierent angles of inclination of the surfaces on said bars which engage the rollers 64, 64. It may be desirable to provide for different lateral displacements of the various portions of the shaft in order to straighten the shaft with a high degree of accuracy. Among other factors, the diameter of the portion of the shaft W within a particular bushing 38 and the wall thickness of said portion must be considered in determining the optimum lateral displacement of the said portion for accurate straightening. After determination of the optimum lateral displacement for each portion of the shaft by experimentation or other means, such displacements may be conveniently provided for by appropriately setting the adjusting screws 78, 78 in the cam bars 70, 70.

When the actuating bar 72 has been moved rightwardly to the position shown in Fig. 2, the said bar is permitted to remain in such position for a selected period of time. During this time period, rotation of the shaft W continues and cold working of the metal of the shaft takes place. At the end of said time period, the actuating bar 72 is moved longitudinally leftwardly at a controlled and comparatively slow rate. The portions of the shaft W in the bushings 38, 38 of the work holders 24, 24 are gradually moved back into longitudinal alignment with each other and with the portions of said shaft in the bushings 38, 38 of the work holders 22, 22, movement of the Work holders 24, 24 occurring between the second position shown in Fig. 2 and the first position shown in Fig. 1. Upon return of the work holders 24, 24 to their said first or normal position, the shaft W, having been accurately straightened, may be removed from the work holders 22, 22 and the work holders 24, 24 by sliding the same leftwardly out of the openings 40, 40 in the bushings 38, 38 of said holders.

As mentioned previously, the radii of curvature of the walls of the openings 40, 40 in the bushings 38, 38 is somewhat critical. The reason for this should now be apparent. If the radius of curvature of the wall of a particular opening 40 is comparatively small, there may be substantially a point contact between said wall at its central portion and the shaft W when the said shaft is bent to an undulating shape as described with the work holders 24, 24 in their second position. Obviously, concentration of stress in the shaft will occur at said point and may result in fracture of the shaft. Conversely, a comparatively large radius of curvature of the wall of an opening 40 may result in substantially point contact between the shaft and said walls at its end portions when the shaft is bent as described. Here again, stress concentration in the shaft isencountered but at two points rather than at a single point. Obviously, the risk of shaft fracture is high. Thus, it will be seen that judicious selection of the radii of curvature of the walls of the openings 40, 44) is essential. By experimentation or other means, the radius of curvature of the wall of each of the openings 40, 40 is determined so as not to be too large or too small andso as to provide for optimum diS- guesses 7 tributi'on of stress in the portion of the shaft to be received by the opening. a

In accordance-with the presently preferred practice, the operation of the straighteningas set out above is effected by power means. That is, the shaft 58 which is rotated to effect rotation of the shaft W. through operation of the gears 56, 56, the gears 52, -2, and the bushings 38, 38 is preferably driven by power, operated means. Similarly, the actuating bar 72 is moved longitudinally as described by power operated means. The gear shaft 53 is shown supported at opposite ends in left and right-hand bearing units indicated generally at 92 and 94 (Figs. 1 and 2). Adjacent the right-hand bearing unit 94, the shaft 58 carries a sprocket 96, as best shown in Fig. 3. Said sprocket is connected by a chain 98 with a sprocket 1'00 mounted on the output shaft of an electric motor 102. The motor 102 is supported on a longitudinally extending platform or shelf 104 fixedly secured to the machine frame 14. Thus, it will be seen that the shaft W may be rotated by energizing motor 102 to drive the gear shaft 58 through the sprocket and chain connection 96, 93 and 100. Operation of the motor 102 may be controlled by a suitable electrical control system.

As best illustrated in Fig. 3, the actuating bar 72 has a longitudinally extending series of teeth 106 formed along its lower surface. A gear 103 having complementary teeth is supported for rotation about a stub shaft 110 carried by a bracket 112. The bracket 112 is secured to the frame 14 of the machine by suitable screws 114, 114. The gear 108is rotated by a longitudinally extending rack 116 which is mounted on the projecting end of a plunger 11% of a conventional air cylinder 120.- A limit switch 122, adapted to be operated by movement of the rack 116, serves a purpose to be set out hereinafter.

It will be apparent that the air cylinder 120 may be operated to move the rack 116 leftwardly from the position shown in Fig. 3 whereby to rotate the gear 108 in a clockwise direction and to thus drive the actuating bar 72 rightwardly. Conversely, movement of the air cylinder plunger 118 and the rack 1'16 rightwardly will result in leftward movement of the actuating bar 72. As shown in Fig. 3, the rack 116 is at the limit of its rightward movement and in such position the said rack is effective to maintain the actuating bar 72 and the work holders 24, 24 in the positions shown in Fig. 1. When so positioned, the rack 116 also operates the limit switch 122 to open the same, the said switch being normally closed.

The air cylinder 120 is controlled in its operation by a solenoid operated valve 123, the said valve being connected in conventional fashion to the cylinder 120 on opposite sides of its piston by conduits 128 and 130 respectively. A supply conduit 132 for the valve 123 is connected with a source of pressurized air not shown. The solenoid operated valve 123 may be of a conventional type having two solenoids 124 and 126 which respectively move the valve to first and second positions when ener gized. As shown, the valve 123 is adapted to be moved to a first position wherein it pressurizes the conduit 128 and vents the conduit 130 when its solenoid 124 is energized. Leftward movement of the rack 116 and rightward movement of the actuating bar 72 results when the said conduits are so connected. When the solenoid 126 is energized, the valve 123 is moved to a second position wherein the conduit 130 is supplied with pressurized air from the conduit 132 and the conduit 128 is vented. This results in rightward movement of the rack 116 and leftward movement of the actuating bar 72. Thus, it will be seen that energization of the solenoid 124 will cause movement of the actuating bar 72 rightwardly and lateral movement of the work holders 24, 24 to their second positions for bending the shaft W. When the solenoid :126 is energized, the actuating bar 72 will be moved leftwardly to return the work holders 24, 24 to their first position shown in Fig. l. a

As previously mentioned, the portions of the shaftW m the bushings 3s, as of the workholders 24, 24 are moved laterally back into longitudinally alignment with each other and with the remaining portions of the shaft at a controlled and comparativelyslow rate afte'r'bending of the shaft. Control of the rate of lateral movement of the work'holders 24, 24 may obviously be exercised by regulating the operation of the air cylinder More' specifically, by regulating the rate of rightward move ment of the air piston of said cylinder and thus the rate of rightward movement of the rack 116', the desired con trol may be exercised. In accordance with the presently preferred practice, controlled and comparatively slow return movement of the work holders '24, 24 from their second to their first or normal position is so effected. The air cylinder120 is of the type including an oil 'cham her which contains an oil piston connected with the air piston'in the cylinder and movable therewith. A conduit 134 having a valve 136 disposed therein is connected with the oil chamber on opposite sides of the oil piston. The valve 136, which may be of a conventional type, is adapted to permit the oil in the chamber to flow freely through said conduit from the left to the right side of the oil piston when the said piston is moved leftwardly with the air piston. When the oil piston moves rightwardly with the air piston, the valve 136 restricts oil flow through the conduit 134 from the right to the left: side of the oil piston whereby to limit the rate of movement of said piston and thus limit the rate of movement of the air piston, the rack 116 and the actuating bar 72 as required. Adjustment of the valve 136 may, of course, be effected to provide various desired rates of leftward movement of the actuating bar 72 whereby to provide for various desired rates of movement of the work holders 24, 24 from their second to their first position. i

Preferably, 'the straightening machine also includes ejecting means whereby shafts, such as the shaft W or other work-pieces, may be conveniently removed from the machine after straightening thereof. As shown, the said ejecting means comprises a conventional air cylinder 138 which is supported by a cross member 140 secured to the ends of the clamping bars 30, 30 at the right-hand end of the machine. The air cylinder 138 has a small cone-shaped member 142 fixedly secured to the projecting end of its plunger (Figs. 1 and 2). The member 142 is adapted to partially enter the shaft W at its smaller end and urge said shaft leftwardly and out of the work holders when the air cylinder is actuated to efifect a power stroke of its plunger (leftward movement of the plunger in Figs. 1, 2 and 3). Operation of the air cylinder 138 is 'controlled by a conventional solenoid operated valve 144. The valve 144 is connected to said cylinder by a conduit 146 and is connected to the aforementioned supply conduit 132 by a conduit 148. Instantaneous energization of the valve solenoid results in operation of the valve which effects a single power stroke of the piston and plunger of the air cylinder and a single return stroke thereof.

As best illustrated in Fig. 3, a normally open limit switch 150, operatively associated with the solenoid operated valve 144, is adapted to be operated by the actuating bar 72. More specifically, the said'switch is adapted to be closed instantaneously by the actuating bar 72 as the bar completes a leftward movement returning the work holders 24, 24 from their second to their first or normal position.

Obviously, an electrical control system for the straightening machine may take 'a variety of forms. An exemplary electrical control system is shown in Fig. 6 in diagrammatic or schematic form. First and second lead lines L1 and L2 in the control system may be connected with a suitable source of power not shown. The aforementioned solenoid 124, associated with the valve 123, is connected in a first conductor 152 extends between the lead lines L1 and L2. Connected in circuit with the solenoid 124 is a normally closed switch 154 which is adapted to be opened by a, timer 156. Also connected in 9 circuit with the solenoid 124 and in circuit with the switch 154 is a switch 158. The switch 158 is normally open and is adapted to be closed manually. A control button 160, shown in Figs. 1 through 3, in a control box 162 at the left-hand end of the straightening machine may be depressed to close the normally open switch 158.

The timer 156 is connected in a second conductor 164 which extends between the lead lines L1 and L2. The aforementioned electric motor 102 and the normally open limit switch 122 are connected in circuit with the timer 156. A third conductor 166 extending between the lead lines L1 and L2 has connected therein the solenoid 126 associated with the valve 123. Also connected in the conductor 166 in circuit with the solenoid 126 is a normally open switch 168. The switch 168 is adapted to be closed by the timer 156. A fourth conductor 170 extending between the lead lines L1 and L2 has a solenoid 172 connected therein. The solenoid 172 operates the valve 144 associated with the air cylinder 138 in the manner described above. Connected in circuit with the solenoid 172 is the aforementioned normally open limit switch 150 which is closed by the actuating bar 72.

Cyclic operation of the straightening machine is effected by the electrical control system in the manner described below. A shaft W is placed in the Work holders 22, 22 and the work holders 24, 24 as described with the latter work holders in their first position as shown in Fig. l. The control button 160 is then depressed for an instaut and released. The switch 158, being thus closed instantaneously, causes the solenoid 124 to be energized instantaneously through the normally closed switch 154. Instantaneous energization of the solenoid 124 causes the valve 123 to be moved to its first position and the air cylinder 120 thereupon initiates leftward movement of the rack 116 and rightward movement of the actuating bar 72. As the leftward movement of the rack 116 is initiated, the normally open limit switch 122 is allowed to close to energize the timer 156 and start electric motor 102. Thus, the shaft W is caused to rotate and the work holders 24, 24 begin to move from their first or normal position to their second position (Fig. 2) whereby to bend the shaft to an undulating shape from end to end. Upon reaching their second position, the work holders 24, 24 remain thereat for a selected period of time as determined by the setting of the timer 156. At the end of the said time period, the timer 156 operates to open the normally closed switch 154 and to close the normally open switch 168. Closing of the switch 168 results in energization of the solenoid 126 and in movement of the valve 123 to its second position. The air cylinder 120 is then caused to move the rack 116 rightwardly and the actuating bar 72 leftwardly at a controlled and comparatively slow rate as described and the work holders 24, 24 are moved laterally from their second to their first position.

On completion of the rightward movement of the rack 116, the normally closed limit switch 122 is opened by the rack 116. As a result of opening of the said switch, the timer 156 is deenergized permitting the switch 154 to assume its normally closed position and permitting the switch 168 to assume its normally open position. Opening of the switch 122 also terminates operations of the motor 10-2 and thus terminates rotation of the shaft W. n termination of rotation of the shaft W, the actuating bar 72 closes the limit switch 150 energizing the solenoid 172. Energization of the solenoid 172 results in operation of the valve 144 and in a power stroke of the piston and plunger of the air cylinder 138. Thus, the shaft W is ejected from the straightening machine and a second shaft to be straightened may be thereafter positioned in the work holders whereupon the control button 160 may be depressed to initiate a succeeding cycle of machine operation.

Figs. 7 through 10 illustrate the construction of work holders and certain associated parts of an alternative straightening machine construction.

The parts of the straightening machine not shown in these figures may be substantially identical with corresponding parts of the straightening machine described above. In this alternative construction, provision is made for longitudinal adjust ment of each of the work holders of the machine to per mit straightening of various sizes of tapered shafts of tubes similar to the shaft W, there being substantial variation in the optimum longitudinal spacing between adjacent work holders for shafts of different sizes. It will be obvious that the principles embodied in the alternative straightening machine constructions, and shown in Figs. 7 through 10, may be embodied readily in other straightening machines constructed in accordance with the invention, but which are not particularly adapted to accommodate tapered shafts similar to the shaft W.

A laterally movable work holder 24a shown in Figs. .7 and 8 may be taken as representative of a plurality of laterally movable work holders in the alternative straightening machine. The said holder 24a has a base portion 34:: similar to a base'portion 34 of a work holder 24. An upright housing portion 36a of the work holder 24a is substantially identical with the corresponding portion 36 of a work holder 24. In addition, the parts within the housing portion 36a, including bearing units 44a, 44a and a bushing 38a, are substantially identical with corresponding parts in a Work holder 24. The base portion 34a of the work holder rests on a substantially fiat surface 12a of the machine frame.

Lateral sliding movement of the work holder 24a is: effected in substantially the same manner as in the case of a work holder 24. However, a cam roller 64a as-- sociated with the holder 24a is adapted for rotation about:

a horizontally disposed pin 66a rather than a vertical pin.. A cam bar 70:: operatively associated with the roller 64a extends vertically rather than horizontally and has a vertical groove 174 provided therein. The groove 174 receives a peripheral portion of the roller 64a and its side walls engage opposite radial faces of the roller so that longitudinal movement of said roller will effect similar longitudinal movement of the said cam bar. The cam bar has an adjusting screw 78a and a binder screw 80:: associated therewith, the function of said screws corresponding to the function of the screws 78 and 80. A dowel 76a is partially received in a suitable recess 74a in the cam bar 70a and partially received in a suitable recess in an actuating bar 72a. The actuating bar 72a is similar to the actuating bar 72 and corresponds in function but is movable vertically rather than longitudinally. Downward movement of the bar 72a efiects movement of the work holder 24a from a first position to a second position, said positions corresponding to the first and second positions of a work holder 24. Upward movement of the cam bar 72a effects a reverse or return movement of the work holder 24a.

On the side of the work holder base 34a opposite the roller 64a, there is provided a biasing spring 82a. The said spring is disposed within a suitable opening 176 in the base portion 34a of the holder and urges the work holder laterally so that its roller 64a is held in engagement with the cam bar 70a. One end of the spring 82a engages a vertical surface 178 on said base portion 34a and the other end thereof engages a vertical surface 189 on a longitudinally extending member 182 which is fixedly secured to the machine frame as by suitable welding.

The longitudinally extending member 182 has a longitudinally extending dovetail groove 184 formed therein however, be moved laterally relative to the guide and supportmember 186. A binder screw extends vertically "through a suitably threaded opening 192 in the guide and support member 186 into engagement with the base wall of the groove 184 and may be tightened' to securethe said member against'longitudinal movement.

From the foregoing, it will be apparent that the work holder 24a may be conveniently adjusted longitudinally for the purpose mentioned. Upon loosening of the binder screw 190, longitudinal movement of the holder 24a to a desired position may be etfected. The guide and support member'186 may be moved longitudinally with the holder, its aforementioned dovetail portion sliding in the slot 184. The cam bar 7ita will also be moved longitudinally with the work holder by engagement of one of the lateral surfaces of the roller 64:: with the adjacent wall of the groove 174 in said bar. The pivot pin or dowel 76a may obviously be fixed to the cam bar 70a so as to slide longitudinally in its recess in the actuating bar 72a therewith. When the work holder and its associated parts are located at the desired longitudinal position, the binder screw 190 may be tightened to secure the said holder and said parts against unintended or accidental longitudinal movement.- Thereafter, the actuating bar 72a'may' be moved vertically to effect the required lateral sliding movement of the work holder.

In Figs. 9 and 10 of the drawings, there is shown a work holder 220 which may be taken as representative of a plurality of laterally fixed work holders in the alternative straightening machine construction. The work holder 22a has a base portion 26a similar to a base portion 26 of a work holder 22 and said Work holder also has anupwardly extending housing portion 28a. The housing portion 28a is substantially identical with a portion 28 of a work holder 22 and parts disposed therein including bearing units 44a, 44a, a bushing 38a, and a gear 52a are substantially identical with corresponding parts of a work holder 22. The gear 52a meshes with and is adapted to bedriven by a gear 56a supported on a shaft 580. The gear 56a may be identical with the aforementioned gears 56, 56 but is connected with the shaft 58a so as to be adjustable longitudinally there-along. V.

A key 194 is disposed partially in-a suitable keyway 196 in the gear 56a and partially in a suitable keyway 198 in the shaft 58a. The keyway 198 in the shaft 58a is of sufficient length to permit substantial longitudinal adjustment of the gear 56a. Thus, longitudinal adjustment of the work holder 22a may be effected without interruption in the driving connection between the gears 52a and 56a. To allow for longitudinal adjustment of the gear 56a, a longitudinally extending slot 200 is provided in the portion of the machine frame which forms the fiat surface 12a.

7 In order to provide for securement of the work holder 22a in an adjusted longitudinal position, a dovetail slot 202 is formed in the aforementioned frame portion. A small dovetail slide 204 adapted to enter and substantially fit the slot 202 has a threaded vertical opening 206 formed therein. The said opening is adapted to receive a binder screw 208 which extends downwardly through a suitably threaded opening 210 in the base por tion 26a of the work holder 22a.

From the foregoing, it will be apparent that longitudinal adjustment of the work holder 22a for the purpose mentioned may be conveniently effected. Upon loosening the binder screw 208, the work holder 22a may be moved to a desired longitudinal position, the slide 204 being moved therewith along the groove 202. The gear 56a may be similarly moved to properly engage the gear 52a whereupon the binder screw 208 may be tightened to secure the work holder against unintended or accidental longitudinal movement.

Operation of the alternative straightening machine may obviously be substantially identical with that described above, for the straightening machine of Figs. 1-6. The only significant change in operation encountered. is the addition of a set-up operation where shafts to be straighb ened vary in size. That is, longitudinal adjustment of the work holders 22a,'22a and the work holders 240', 24a will ordinarily. berrequired when changing from a shaftW of one size t'o a' shaft W of another size.

The invention claimed is:

1. In a machine for straightening elongated workpieces of non-uniform cross section throughout their length, the combination of at least three work holders in longitudinal series respectively adapted to engage successive longitudinally spaced portions of a non-uniform workpiece and collectively adapted to elfect longitudinal alignment of said workpiece portions and relative lateral displacement'thereof without substantial endwise movement of the workpiece. and means for rotating the workpiece while its said portions are longitudinally aligned and while they are relativelydisplaced laterally.

2. In a machine for straightening elongated workpieces of non-uniform cross section throughout their length, the combination of at least three work holders in longitudinal series respectively adapted to engage successive longitudinally spaced portions of a non-uniform workpiece and collectively adapted to effect longitudinal alignment of said workpiece portions and relative lateral displacement thereof without substantial endwise movement of the workpiece, at least one of said work holders being adapted to rotate the workpiece while its said portions are longitudinally aiigned and while they are relatively displaced laterally.

31 In a machine for straightening elongated workpieces of non-uniform cross section throughout their length, the combination of at leastthree work holders in longitudinal series respectively adapted to engage successivelongitudinally spaced portions of a non-uniform workpiece and collectively adapted to eifect longitudinal alignment of said workpiece portions and substantially linear relative lateral displacement thereof approximately in a common plane without substantial endwise movement of the workpiece, and means for rotating the workpiece while -its said portions are longitudinally aligned and while they are relatively displaced laterally.

4. In a machine for straightening elongated workpieces of non-uniform cross section throughout their length, the combination of at least three work holders in longitudinal series respectively having openings adapted to receive and substantially fit successive longitudinally spaced portions of a non-uniform workpiece and collectively adapted for relative lateral movement so as to effect longitudinalalig'nmentof said workpiece portions and relative lateral displacement thereof without substantial endwise movement of the workpiece, and means for rotating the workpiece while its said portions are longitudinally aligned and while they are relatively displaced laterally. v

5. In a machine for straightening elongated Workpiec'es of non-uniform cross section throughout their length -the' combination of at least three work holders in longitudinal serieseach provided with a rotatable member having alongitudinally extending opening, said openings being adapted respectively to receive and substantially fit'successive' longitudinally spaced portions of a non-uniform workpiece, and said work holders being adapted for relative lateral movement so as to effect longitudinal alignment of said workpiece portions and relativelateraldisplacement thereof without substantial endwise movement of th e workpiece, and means operatively connected with at least one of said rotatable memnon-uniform workpiece, said work holders being adapted for relative lateral movement so as to effect longitudinal alignment of said workpiece portions and relative lateral displacement thereof without substantial endwise movement of the workpiece whereby said workpiece assumes an undulatory shape from end to end, and means for rotating the workpiece while its said portions are longitudinally aligned and while they are relatively displaced laterally.

7. In a machine for straightening elongated workpieces of non-uniform cross section throughout their length, the combination of a plurality of work holders comprising first and second groups of work holders arranged alternately in a longitudinal series, the work holders of said first and second groups being respectively adapted to engage successive longitudinally spaced portions of a nonuniform workpiece, each of the work holders of said first group being secured against lateral movement so that portions of a workpiece engaged by said holders are held in longitudinal alignment, and each of the work holders of said second group being movable laterally so that portions of the workpiece engaged by said holders may be moved laterally in and out of longitudinal alignment with the portions thereof engaged by the work holders of said first group, and means for rotating the workpiece during movement of the work holders of said second group.

8. In a machine for straightening elongated workpieces of non-uniform cross section throughout their length, the combination of a plurality of work holders comprising first and second groups of work holders arranged alternately in a longitudinal series, the work holders of said first and second groups each comprising a rotatable member provided with a longitudinal opening which openings are respectively adapted to receive and substantially fit successive longitudinally spaced portions of a non-uniform workpiece, each of the work holders of said first group being secured against lateral movement so that portions of a workpiece in their rotatable members are held in longitudinal alignment, and each of the work holders of said second group being movable laterally so that portions of the workpiece in their rotatable members may be moved laterally in and out of longitudinal alignment with the portions thereof in the rotatable members of said first group of work holders, and means operatively connected with at least one of the work holders of said first group and adapted to drive the rotatable member thereof whereby to rotate the workpiece.

9. In a machine for straightening elongated workpieces of non-uniform cross section throughout their length, the combination of a plurality of work holders comprising first and second groups of work holders arranged alternately in a longitudinal series, the work holders of said first and second groups each comprising a rotatable member provided with a longitudinal opening which openings are respectively adapted to receive and substantially fit successive longitudinally spaced portions of a non-uniform workpiece, each of the work holders of said first group being secured against lateral movement so that portions of a workpiece in their rotatable members are held in longitudinal alignment, and each of the work holders of said second group being movable laterally so that portions of the workpiece in their rotatable members may be moved laterally in and out of longitudinal alignment with the portions thereof in the rotatable members of said first group of work holders, power operated means for moving said second group of work holders from a first position wherein the workpiece is straight to a second position wherein the workpiece is bent to an undulating shape from end to end and then back to said first position, and means operatively connected with at least one of the work holders of said first group and adapted to drive the rotatable member thereof whereby to rotate the workpiece during operation of said power operated means.

10. A machine adapted to straighten elongated workpieces of non-uniform cross section throughout their length, said machine comprising a longitudinal frame, a plurality of work holders supportedby the frame in a longitudinal series, said plurality of work holders including first and second groups of'work holders arranged alternately in said longitudinal series, each of the work holders of both groups having a rotatable member provided with a longitudinal opening which openings are respectively adapted to receive and substantially fit suc cessive longitudinally spaced portions of a non-uniform workpiece, each-of the work holders of the first group being fixed against lateral movement so that portions of the workpiece in their rotatable members are held in longitudinal alignment, and each of the work holders of the second group being supported for substantially rectilinear lateral movement so that portions of the workpiece in their rotatable members may be moved laterally approximately in a common plane in and out of longitudinal alignment with the portions thereof in the rotatable members of said first group of work holders, power operated means supported by said frame adapted to move said second group of work holders substantially in unison from a first position wherein the workpiece is straight to a second position wherein the workpiece is bent to an undulating shape from end to end and then back to said first position, and means supported by said frame and operatively connected with at least one of the work holders of said first group and adapted to drive the rotatable member-thereof whereby to rotate the workpiece during operation of said power operated means.

11. A machine adapted to straighten elongated workpieces of non-uniform cross section throughout their length, said machine comprising a frame having a longitudinally extending substantially horizontal flat surface, a plurality of work holders supported on said surface in a longitudinal series, said plurality of work holders including first and second groups of work holders arranged alternately in said longitudinal series, each of the work holders of both groups including a rotatable member provided with a longitudinal opening which openings are respectively adapted to receive and substantially fit successive longitudinally spaced portions of a non-uniform workpiece, each of the work holders of the first group being secured to said frame so as to be fixed against lateral movement with the portions of the workpiece in their rotatable members held in longitudinal alignment, and each of the work holders of the second group being slidable laterally on said frame surface so that portions of the workpiece in their rotatable members may be moved laterally in and out of longitudinal alignment with the workpiece portions in the rotatable members of said first group of work holders, biasing means supported by said frame tending to hold the work holders of said second group in a first position wherein the workpiece is held straight, power operated cam means supported by said frame adapted first to move said second group of work holders substantially in unison from said first position to a second position wherein the workpiece is bent to an undulating shape from end to end and then to permit said biasing means to return said work holders to said first position, and means supported by said frame and operatively connected with at least one of the work holders of said first group and adapted to drive the rotatable member thereof whereby to rotate the workpiece during operation of said power operated cam means.

12. A machine adapted to straighten elongated workpieces of non-uniform cross section throughout their length, said machine comprising a frame having a longitudinally extending substantially horizontal flat surface, a plurality of work holders supported on said frame sur face in a longitudinal series, said plurality of work holders including first and second groups of work holders arranged alternately in said longitudinal series, each of the work holders of both groups including a rotatable memher provided with'a longitudinal opening which openings are respectively adapted to receive and substantially fit successive longitudinally spaced portions of a non-uniform workpiece, eachofthe work holders of the first group being secured to said frame so as to be fixed against lateral movement with the portionsof the workpiece in the rotatable members thereof held in longitudinal alignment, and each of the work holders of the second group being slidable laterally on said framesurface and being provided at; one side with a cam follower, resilient biasing means operatively associated with eachof the work holders of said second group, a plurality of cams operatively associated respectively with the cam followers of said laterally slidable work holders and opposing said biasing means, power operated means for actuating said cams in unison so that said slidable w'ork holders are moved laterally from a first position wherein the workpiece is straight to a second position wherein the workpiece is bent to an undulating shape from end to end and then back to said first position, and means supported by said frame and operatively-connected with at least one of the work holders of said first group and adapted to drive the rotatable member thereof whereby to rotate the workpiece during operation of said power operated means.

13. A. straightening machine as set forth in claim 12 wherein the cams associated with the followers of the laterally slidable work holders are adapted to eifect different lateral displacements of at least some of said work holders in their said second positions.

14. A machine adapted to straighten elongated workpieces of non-uniform cross section throughout their length, said machine comprising a frame having a longitudinally extending substantially horizontal flat surface, a plurality of work holders supported onsaid frame surface in a longitudinal series, said plurality of work holders including first and second groups of work holders arranged alternately in said longitudinal series, each of the work holders of both groups including a rotatable member provided with a longitudinal opening which openings are respectively adapted to receive and substantially fit successive longitudinally spaced portions of a nonuniform workpiece, each of the work holders of the first group being secured to said frame surface so as to be fixed against lateral movement'with the portions of the workpiece in the rotatable members thereof held in longitudinal alignment, and each of the work holders of the second group being slidable laterally on said frame surface and being. provided atone side with a cam follower, a spring means operatively associated with each of the work holders of said second group on the side opposite the cam follower, a longitudinally extending cam actuating bar supported by said frame adjacent the followers on said laterally slidable work holders, a plurality of cams connected to and spaced longitudinally along said bar so as to be disposed respectively adjacent said cam followers, each of said cams having a flat surface engaging its corresponding follower and which is inclined to provide for lateral displacement of the follower and its associated work holder with longitudinal movement of said actuating bar, adjusting means associated with each of said cams and adapted to'vary the angle of inclination of the fiat surface thereof independently of the angles of inclinations of the similar surfaces of the remaining cams, power operated means for moving said actuating bar longitudinally whereby to actuatesaid cams in unison so that said slidable work holders are moved laterally from a first position wherein the workpiece is straight to a second position wherein the workpiece is bent to an undulating shape from end to end and then back to said first position, and means supported by said frame and operatively connected with each of the work holders of said first group and adapted to drive the rotatable members thereof whereby to rotate the workpiece during operation of said power operated means.

1 15." In a machine for straightening elongated workpieces of non-uniform cross 1 section throughout their length, the combination of a plurality of work holders comprising first and second groups vof holders arranged alternately in 'a longitudinal series, each of the work holders of said first and second groups being adapted for longitudinal adjustment and said work holders being respectively adapted to engage successive longitudinally spaced portions of a non-uniform workpiece, each of the work holders of said first group beingsecured against lateral movement so that portions of a workpiece engaged thereby are held in longitudinal alignment, and each of the work holders of said second group being movable laterally so that portions of the work piece engaged thereby may be-selectively moved into and out of longitudinal alignment with the portions thereof engaged by the work holders of said first group, and means for rotating a workpiece substantially about its longitudinal centerline while the workpiece is engaged by said work holders, said last mentioned means being effective to rotate the workpiece regardless of longitudinal adjustment and lateral movement of the work holders.

16. Amachine adapted to straighten elongated workpieces of non-uniform cross section throughout their length, said machine comprising a frame having a longitudinally extending substantially horizontal fiat surface, a plurality of work holders supported on said frame surface in a longitudinal series, said plurality of work holders including first and second groups of work holders arranged alternately in said longitudinal series, each of the work holders of both groups being adapted for longitudinal adjustment and including a rotatable member provided with a longitudinal opening which openings are respectively adapted to receive and substantially fit successive longitudinally spaced portions of a non-uniform workpiece, the work holders of. the first group being secured to said frame surface so as to be fixed against lateral movement and to hold portions of the workpiece in their rotatable members in longitudinal alignment, and the Work holders of the second group being slidable laterally on said frame surface so that portions of the workpiece in their rotatable members may be moved into and out of longitudinal alignment with the workpiece port-ionsin the rotatable members of said first group of work holders, biasing means adjustable longitudinally with the work holders of said second group and adapted to bias the same toward a first position wherein the workpiece is held straight, power operated cam means supported by said-frame adapted first to move said second group of work holders substantially in unisonfrom said first position to a second position wherein the workpiece is bent to an undulating shape from end to end and then to permit said biasing means to return said work holders to said first position, and means supported by said frame and operatively connected with at least one of the work holders of said first group and adapted to drive the rotatable member thereof whereby, to rotate the workpiece during operation of said power operated cam means.

17'. A machine adapted to Straighten elongated workpieces of non-uniform cross section throughout their length, said machine comprising a frame having a longitudinally extending substantially horizontal fiat surface, a plurality of work holders supported on said frame surface in a longitudinal series, said plurality of work holders including first and second groups of work holders arranged alternately in said longitudinal series, each of the Work holders of both groups being adapted for longitudinal adjustment and including a rotatable member provided with a longitudinal opening which openings are respectively adapted to receive and substantially fit successive longitudinally spaced portions of a non-uniform workpiece, each of the work holders of the first group being secured to said frame surface so as to be fixed against lateral movement with the portions of the workpiece in the rotatable members thereof held in longitudinal alignment, and each of the work holders of the second group being slidable laterally on said frame surface and being provided at one side with a cam follower, a spring means engaged with and longitudinally adjustable with each of the work holders of said second group on the side opposite the cam follower, a longitudinally extending cam actuating bar supported by said frame adjacent the followers on said laterally slidable work holders, a plurality of cams connected to and spaced longitudinally along said bar so as to be disposed respectively adjacent said cam followers, each of said cams having a flat surface engaging its corresponding follower and which is inclined to provide for lateral displacement of the follower and its associated work holder with movement of said actuating bar, adjusting means associated with each of said cams and adapted to vary the angle of inclination of the flat surface thereof independently of the angles of inclination of the similar surfaces of the remaining cams, power operated means for moving said actuating bar whereby to actuate said cams in unison so that said slidable work holders are moved laterally from a first position wherein the workpiece is straight to a second position wherein the workpiece is bent to an undulating shape from end to end and then back to said first position, and means supported by said frame and operatively connected with each of the work holders of said first group and adapted to drive the rotatable members thereof whereby to rotate the Workpiece during operation of said power operated means.

18. The combination in a straightening machine of a plurality of work holders comprising first and second groups of work holders arranged alternately in a longitudinal series, the work holders of said first and second groups each comprising a rotatable member provided with a longitudinal opening which openings are respectively adapted to receive and substantially fit successive longitudinally spaced portions of an elongated workpiece, each of the work holders of said first group being secured against lateral movement so that portions of a workpiece in their rotatable members are held in longitudinal alignment with each other, and each of the work holders of said second group being movable laterally so that portions of the workpiece in their rotatable members may be moved laterally in and out of longitudinal alignment with the portions of said workpiece in the rotatable members of the first group of work holders, and means operatively connected with at least one of the work holders of said first group and adapted to drive the rotatable member thereof whereby to rotate the workpiece with the said portions thereof in the rotatable members of the work holders respectively turning about the axes of the rotatable members of the work holders irrespective of lateral movement of the work holders of said second group.

References Cited in the file of this patent UNITED STATES PATENTS 523,497 Wick July 24, 1894 617,223 Brightman Jan. 3, 1899 683,109 Dutton Sept. 24, 1901 1,017,645 Brightman Feb. 20, 1912 1,190,698 Abramsen July 11, 1916 1,657,311 Malone J an. 24, 1928 

